The overall objectives for this project are to develop methods which can be effectively used to alter the leukemic process. We are developing methods of early biochemical diagnosis of acute lymphoblastic leukemia by use of chemical markers present in proliferating cells. One such marker of special interest is taurine, an acidic biogenic amine. We are investigating the role or roles of taurine, and its precursors, in the control of cellular proliferation in normal as well as leukemic cells. We have, or will, study several aspects of these compounds; a) whether the intracellular concentration of these compounds can be used to gauge the proliferative state of the leukemic process or its maturation; b) whether changes in taurine content (per cell) (concentration) (per mg DNA or mg Protein) or that of its precursors, during the course of experimental manipulation will relate in any way to tumor volume and/or proliferative capacity; c) whether known specific agents which alter taurine metabolism might alter the leukemic process or cellular proliferation as well. Understanding the basic processes involved in normal cell proliferation will bring us closer to providing answers to the problem of control of acute and chronic leukemias. We hope that this approach will provide new avenues to the management of these difficult clinical problems.